Beginner question - please help

This is a discussion on Beginner question - please help within the C++ Programming forums, part of the General Programming Boards category; I am asked this question as part of an assignment, and I have no clue what to say:
What is ...

I think the issue here is encapsulation. You can set the values of all the variables cause they're defined as public members. There should be setter functions of some description which set the points and then recalculates the length between the points. If you have a point at (0,3) and another at (4,0) and the length between them as 5 and you were then to change the first point to (4,0), there's no way the code would change the length to zero. It would still say five. If you had a function which managed the changing of the variables it could calculate the new length on every change.